Thick sinus membrane or D4 bone?

Dr. N asks:
Please see the case photos below. Tooth #14 was extracted 6 weeks previously uneventfully. 4 wall defect, e-PTEF Cytoplasm membrane and Puros allograft placed. Healing uneventful as well. 6 weeks later CBCT shows following readings. Is this really bone, all-be-it D-4 or is this just a very thick sinus membrane? See attached CBCT @3 film.

Bone density reading #14

Coronal view #14

Saggital view #14

35 thoughts on “Thick sinus membrane or D4 bone?

  1. peter fairbairn says:

    In your computer placement guide you are placing into the the thickenned lining , seen very often in fact in most scans there is a thickened lining to some degree.
    Not an issue unless severe with possibility of blocking the Ostium. Many causes of this thickenning from smoking to pollution but not an issue and generally indicates that the lifting will be easier and less prone to a tear of the lining.
    My estimation is that you have about 4 mm of bone at your designated point of placement.
    The thickenning will yary constantly and you could use decongestants prior to lifting.
    Diagnotic tools are great but must able to analize them

  2. OMS resident says:

    I think it is unethical to use a CBCT when you’re not able to read the images and take advantage of the diagnostic potential. To me it shows lack of competence and I would not recommend you to do the future implant surgery at #14. Send the patient to your local OMS. Good luck!

  3. Dr Mario Marcone says:

    To my friend OMS resident,

    In my honest opinion, sir, I will politely tell you that your comment may be considered by many to be extremely distasteful and insulting to our colleague and to the profession. I think you should retract it, and our colleague, who is just looking for some input, deserves an apology. This forum is designed for all of us. And, may I add, what makes you think that OMS are the only dental professionals able to read a CT and place implants?!
    Let us conduct ourselves professionally! Dentistry does not need this kind of attitude.

    May God help us all

  4. Sb oms says:

    To the oms resident, if you act like this when you are in the real world, you will have a pretty slow practice. Trust me.
    As dr fairbaum said, you have 3-4 mm of bone and a thick sinus membrane. I would do a small lateral lift, others would do a crestal lift. The membrane thickening is not pathologic as it does not take up much of the sinus or block the ostium. It should be noted however as this patient will be prone to congestion following surgery.
    In cases like this, I am now doing the sinus lift when I take out the tooth.

  5. OMS resident says:

    First of all I apologize if I stepped on anybodies toes. Drs N and Marcone, I’m sorry if I offended you!

    My great concern is just that the relatively new cone beam technology is somehow misused by all genres of dentists, both specialists and general practitioners. The sales numbers of these machines have exploded over the last few years, and as dental/medical professionals we should think about the proper indications for cone beam imaging in general.

    I’ve been working with cone beam imaging and conventional CT scans for many years, and it has taken me (and my colleagues) a lot of time to acquire the necessary competence required to use these as valuable tools in diagnostics and in treatment planning/evaluation.

    Regarding implant placement, I know that there are a lot of competent colleagues out there, both OMS, periodontists and GDPs. But (and this calls for all of us) if we’re not able to manage certain dental/surgical procedures, we should refer these cases to a more competent colleague. This is in the best interest of our patients. Case closed:)

    Best regards,

    Dr. H, OMS resident

  6. Ziv Mazor says:

    Hi Dr N,
    First and to the point you have approximately 3mm of residual bone.You have a thickened sinus membrane which in your case makes the elevation easier with less risk of membrane perforation.You have two options of lifting the membrane- either a lateral window or a MIAMBE-minimal invasive antral membrane balloon elevation approach(which is my current preference).
    As for the other debate…I totally agree with Dr Marconi.

  7. M. Maningky says:

    To some degree our young resident friend has a point.
    Technology is as good as the one who uses it.
    Based on this image it is impossible to say that the thickening is not pathologic. The only way to find out is to ask the patient wether he has symptoms of sinusitis.
    In this case it doesnt’t really matter one way or another, if you graft the site properly you don’t have to perforate the sinus. Placing the implant as shown in the planning CT will definitely cause a major problem both prosthetic and with integration. Chances are the implant will be lost in the sinus somewhere and you might need our resident friend 😉

  8. Dr. Gerald Rudick says:

    Dear Confreres,
    The beauty of these forums is that so much information is exchanged between professionals interested in dental implantology…..newcomers and older pros.
    A good lesson was learned by our OMS resident, as the purpose here is not to insult or criticise, but to share your knowledge and experience.
    Cone beam technology was not available when Hilt Tatum was bright enough and had the forsight and imagination to conquer the sinus cavity and showed us how to make it useful.
    Dentists,oral surgeons, periodontists,etc are not experts in radiology and can misinterpret a scan.
    Scans are wonderful and have their place, but is it fair to our patients to subject them to so much radiation, when most of the information can be derived from gentle probing with osseotomes and taking good radiographs.
    My advice to Dr. N, is to fill your graft sites well, and wait at least 16 weeks before attempting to place implants….. you will get a clearer picture of what you have to work with…. and welcome to our exclusive club.

    Dr. Gerald Rudick Montreal

  9. Pankaj Narkhede, DDS; MDS says:

    Dear Dr. N: The bone graft that was placed seems to have diappeared. What you see is a thickened sinus lining. If it was my case I would prefer a sinus augmentation. Pt will on antibiotics and decongestants. Implant placed after 9 mths. If this a single tooth replacement You will have a long crown. Onlay graft advised for esthtics. Pl chck videos on bicon website may help 🙂

  10. Dr FCampos says:

    OUCH Dr H that was cold. Is obvious that you are very young and i do understand you frustration but in the same token we all were young dentist and along the way we learn and learn and learn. This is not an easy case and i do not think that 6 weeks will give us enough mature bone for placing an implant(play safe 2,3 months).Not having a sinus lift will leave very little room to meneuver,but it can be done.maybe a crestal aproach for the lift, if you do not feel confident enough please ask for help from your local OMS/Perio most of the time they’re glad to help us. Best for you and DO NOT STOP

  11. MEU says:

    Hi Dr N: in my opinion, the CBCT pictures are consistent with a Mucous Retention Cyst and I think you only have about 3-4 mm of bone. You may have to consult a radiologist to properly identify the radioopacity and do a proper treatment plan based on a sound diagnosis. It looks to me that you may have to do some bone grafting prior to the implant placemeent. Good luck and hopefully you get advices as opposed to negative criticism. MEU

  12. Manosteel says:

    Looks like a thickened sinus membrane to me. In our area we have a dental cbct service which for $400.00 we get an image on cd along with a written interpretation by a board certified Dental Radiologist.NICE! 2 opinions! To the OMS resident with the attitude: When I was In my graduate program in Prosthodontics we had a passive Chair and a hyper-aggressive, belligerent, sadistic,hypercritical program director who never had a good thing to say to anyone unless it could advance his position politically. He loved destructive criticism in front of an audience!!!Guess what, after a while everyone became hyper clones of him doing the same thing to everyone else! Maybe the same is happening to you?? You have no monopoly on learning believe me! You’ll go much farther especially with GP’s if you become more helpfull, instead of bashing them as bunch of sensless dumbasses. Practitioners who ask questions on this site want constructive advice not destructive criticism in front of an audience of other Dentists!

  13. ben manz says:

    I have a smile rule. where conventional radiology leave a doubt in my mind I go for CBCT. if i still have any doubt just opt for radiologist report.

    We all learn as we go where in doubt seek help. if you do not do sinus grafting and your whole point of socket preservation at extraction was to avoid sinus lift then just refer anyways without any worry.As you know by now it is morelikely thick membrane as idicated by intact sinus floor underneath.

    best regards

  14. B. Muntean says:

    This is often seen with the upper 2nd molars (the sinus most likely rested into the furcation area, before the tooth was extracted). On the other hand, the bone density reading it is puzzling and it’s only been 6 weeks since the extraction. For the posterior maxilla area I suggest waiting 5-6 months before taking another X-ray.

  15. David Goldberg says:

    i have an idea. Call me crazy. How about a bridge?

    PS I’m a periodontist that does 10+ sinus lifts/month and 40-50 implants/ month.

    If it were me I’d get a bridge and forgo the future visit with the ENT o have my sinus scoped and cleared because the mucous retention cyst blocked up my ostium after the OMS did a lateral wall graft.

    BTW that one has a nice Buccal and vertical defect the C:R will be a problem.

  16. Dr J says:

    My Dear OMS resident,
    I applaud you for the courage to speak the truth. But the sad truth is that many incompetent individuals are entering the field of implant dentistry. It is a sad sad thing, but your lively hood depends on them. There will be lots of work from people like that down the road once their cases start failing; so keep your attitude hidden and when they need your expertise be available! I feel your pain when someone who can’t distinguish between soft tissue and bone is placing implants!

  17. Dr Mario Marcone says:

    There is absolutely one looming certain truth here.
    The field of implantology risks becoming a field involved with much troubleshooting.
    I fear that the term “EXPLANTOLOGY” will become a common part of routine treatment planning for a significant number of disgruntled patients.
    It is my conviction that this troubleshooting can only be handled by those practitioners that strive to have a very thorough understanding of the many evolving past and current biologic and scientific concepts that are being researched and developed to this very day.
    There is no menu or “how to” list when it comes to troubleshooting.
    Troubleshooting problems does not necessarily come without a severe cost, to both the patients and the dental practitioners involved.
    The consequences can be devastating at a personal level for all involved.

    We as dental practitioners, who serve people that trust us, must resist adopting the attitude of complacency.
    We have seen the beautiful discovery of implantology now potentially in the hands of every one that has a dental degree.
    We all know that this has been catalyzed by the ambitious business-minded people of the day.
    The truth is … implantology should be practiced by those individuals who have the proper credentials, and to this day, there is still no serious regulation about this.
    We need to protect not just the patients, but also our beloved profession as a whole.
    Who are we fooling here but ourselves.
    If this potentially disastrous trend continues there won’t be any patients left who will want implants!
    I have personally started to study implantology about 5 years ago when I was introduced to Dr Carl Misch.
    At that point, I was 50 years old.
    Many of my colleagues thought I was crazy to take on this endeavor.
    But I persisted because I developed a thirst for knowledge, I wanted to know everything possible so that I could be of reliable service to my patients seeking implant therapy, even if it meant only giving them the proper initial advice and concepts, and, then, directing them to the well trained and experienced practitioners, with whom I’d be able to have an intelligent conversation about the patient’s issues.
    The more I learned, the more I felt ignorant, contrary to what many pushy sales reps wanted me to think.
    I became more and more afraid of not knowing what I didn’t know.
    This field is evolving fast;and, it is challenging to keep current with all the literature, the different ideas, it’s a real mind-boggling monster of a discipline.
    I have travelled all over the USA and parts of Europe, have met many wonderful mentors, have read extensivley on the topic in textbooks, past and current journal literature … etc etc …
    I can confidently say this … when it comes to dental implant therapy, we have not yet quite figured it out yet.
    I pray that whoever wants to render implant therapy to any of those great patients, I hope you are well schooled, and most of all humble enough to know where your limitations lie.
    And, to all those who are in the position of influence, let’s put an end to this looming tragedy … implantology belongs in the hands of individuals who are well trained and schooled … and, then, those individuals should help support one another, unselfishly, and help mentor those that do not know, or have not had the opportunity, to know better, simply because the brainwashing effect of marketing got to them first.
    Let us be patient and professional and proud to have been given this privilege to practice this beautiful profession … our dental degree was only a “license to learn” … let us keep learning and strive for excellence.

    My Dear Colleagues, May God Bless You All

    Dr Mario Marcone, Montreal, Canada
    Fellow of the Academy of General Dentistry
    Fellow of the Misch International Implant Institute
    Fellow of the International Congress of Oral Implantologists

  18. Dr.N says:

    This forum never ceases to amaze me, no telling what type insecurities you might fall upon or what ego you bump up against . My question was a simple one “thicken membrane or D-4 bone?”, that’s all. The scan I took gave a much higher “hounsfield” reading than what I normally get. My impression was that is was a thicken membrane as most of you confirmed. Thanks to all of you, including the young resident. By the way, I have been surgically placing implants for the past 6 years and restoring them since the mid 1990s. I have been well trained with both the Maxi 9 month implant basic course as well as later a 6 month advance implant course. I have my diplomat status with the ICOI, Mastership Status with AGD , Pankey C-6 graduate and I am a student of Pikos/Salama training. The purpose of this forum is to ask questions so that we may all learn. This is what makes Dentistry such an exciting field for me even after 33 years in practice. Thanks for the help

  19. ttmillerjr says:

    Dr. N,
    Your coronal views are the most useful to evaluate crestal bone. You have maybe 1.5mm of bone, look at the palatal and buccal bone, the material of similar density connecting these two is your crestal bone. No way do you have 3-4mm as a few have said. There is clearly inflammation/enlarged sinus membrane, this is what most of your simulated implant is sitting in. Before taking your next step see if you can eliminate this inflammation with antihistamines + decongestants. I recommend 12 or 24 hour antihistamine with decongestant. I also recommend you take some classes dealing with cbct anatomy and diagnosis. Why don’t you find a mentor who you can watch/assist and learn from.

  20. Wleed Haq says:

    You need to get the correct image to analyse the bone in the area of the proposed impplant. Your fisrt image is coronal image, you need to choose an axial image taken through the maxiallary bone and then draw a panoramic curve through that and then you can choose the corresponding sectional image of the bone in the area of the implant. Judging from your images I think that you may have a limited height of bone 1-2 mm with a thickened sinus lining so may need to perfrom a lateral window technique or refer.

  21. john townend says:

    Does anyone have an opinion on the periodontal state of the sole remaining upper molar as seen on the sagittal view? Looks very doubtful to me. Perhaps our knowledgeable OMS resident can help me out here.

  22. OMS resident says:

    I understand that I have provoked Mr. John Townend, but like I said in a earlier comment, I am sorry for my “outburst”.

    To answer his question, what about consulting with a (maxillofacial?) radiologist? Working in collaboration with a radiologist is very helpful, especially in complex cases. When it comes to specific conditions related to teeth and neighbouring structures I’ve had good experiences consulting with oral and maxillofacial radiologists.

  23. M&M says:

    Dear Dr N,

    I agree with some of the posers that the residual alveolar bone height appeared to be only at most 2mm in your scan.
    And the ridge preservation has failed.
    In this scenario, it is more predictable to have a lateral sinus lift and re-enter in 4-6 months time to place the fixture, depending on the type of grafts that you place.
    Also of utmost importance is to check with your patient of any sinusitis s+s that may indicate a non-healthy sinus. Good luck to you!

  24. dr.danesh says:

    dear colleague;
    in this case you need a vertical bone augmentation again,should you use particulated autogenous bone graft
    mixed w/ bio oss and covered w/ ti-reinforced membrain.
    dont forget that you have to wait for 9 months ,(pregnancy period) and then insert your implant.
    if this is your first time ,get the help of an expert ,but for the 2nd time do it alone.

  25. Truth says:

    Bio-Oss is a only filler. Produced by low temperatures. Proteins from cows could be inside which lead to infections. Take resorbable bone substitutes.

  26. john townend says:

    Dear OMS resident.
    Sorry, I couldn’t resist the little dig at you! But more seriously, don’t you think the periodontium around the apex and distal root surface of the sole remaining upper molar (UR6?) looks strange on the sagittal view? Looks to me as though this tooth is floating in space. We don’t have the luxury of an oral and maxillofacial radiologist in my neck of the woods so I would value your opinion.

  27. Dr TC says:

    Dr N – I believe that bone density readings and ‘Hounsfield’ units on CBVTs are not absolute values (such as you might get with a CT) but are relative and without knowing the parameters, are virtually useless. My opinion is that you have a thickened sinus membrane.
    Dr? Townend – regards the max molar – the view you see is not a true sagittal, merely a reformat at some point in space. I make a trick in some of my lectures of making the roots of some teeth ‘disappear’ in one view, then reappear in another. The max molar you see is tilted in a different plane from the reformat, making the root apices invisible. I suggest you obtain a cbvt scan and spend a couple of pleasant hours investigating the many ways you can view structures – a great help when diagnosing cases.

  28. MMT says:

    It is not about OMSs and General practicioners.
    Its about distinguishing soft tissues to hard tissues
    planning your implant placement. If you cant distingush
    one another then you got a problem.

  29. OMS resident says:

    Dear Mr. Townend, I agree that the UR6 region looks a bit strange. I showed the images it to a radiologist, and he meant that it could be something wrong with the reformating in the computer software. His suggestions was either to get better saggital and coronal views by using the “MPR mode” that most CBCT/CBVT softwares have, OR to evaluate the tooth and the periodontium with the combination of plain films and a periodontal probe…

  30. Dr Sanjay Jamdade says:

    The academic discussion here is very interesting. However it’s amusing to read the non academic discussion – all about general dentists and specialists. What has trigered this discussion? Dr N hasn’t said that the extraction/graft was done by him/her. Nor was it claimed that he/she is going to do any sinus lift/implantation him/her self. For all we know it could just be a student! Or a curious family practitioner! What a waste of band width! Why do our imaginations run wild and jump to conclusions. Suppose most of us looked at things objectively at face value without getting into ascribing imaginary motives to original enquiry postings here. Please read original posting carefully word to word.

  31. Dr Sanjay Jamdade says:

    Sorry I am late. I missed it. But it is established that Dr N is a thouroughly trained Implantologist of impeccable credentials but we don’t have evidence whether the patient in the CBCT picture was being/going to be treated by Dr N him/herself or by someone else. There could be myriad of possibilities. Most of the steam let off here is unjustified.


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